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ANALYTICAL
CHEMISTRY
Beckman pioneers another instrumentation advancement. .
SINGLE BEAM
with BECKMAN
direct infrared Transmittancy spectrophotometers recording IMPORTANT ADVANTAGES of the Beckman Transmittancy Recorder
NEW SINGLE BEAM SYSTEM IS SIMPLE, ACCURATE, RELIABLE The Beckman Single Beam Direct Transmittancy Recorder employs the memory standardization principle, using reliable electronic circuits instead of complicated mechanical-optical arrangements. It successfully combines the highest accuracy with the utmost in reliability and convenience. A standardizing run is made on the empty or solvent-filled absorption cell. During this run the signal from the photoreceiver is auto matically maintained constant, and the resulting slit width vs. wavelength function is "memorized" on a wire recorder. The sample is then placed in the same cell, and in formation played back from the wire recorder automatically controls the wavelength and slit drive motors to reproduce precisely the conditions which produced the constant 100% reference level. Any absorption resulting from the sample is accurately and auto matically recorded directly in transmittancy. On repeat runs, the same reference wire is used, eliminating repetition of standardizing measurements. Single beam transmittancy recording retains the excellent resolution, low stray light, high stability and drift freedom, and the wavelength accuracy of the well-known Beckman Spectrophotometers. Other advantages are summarized at the right.
THREE UNEXCELLED INSTRUMENTS FOR ANY REQUIREMENT Beckman Single Beam Direct Transmittancy Recording is available either (1) as an accessory unit for direct installation on any Beckman IR-2 Spectrophotometer, or (2) with the IR-2 as a complete instrument, or (3) in the new unsurpassed Beckman IR-3 Spectrophotometer —the most versatile, most accurate, most complete— and by all standards, the finest spectrophotometer money can buy.* For further information on these instruments write . . .
BECKMAN INSTRUMENTS control modern industries
Beckman Instruments, Inc., South Pasadena 15, Calif. Factory Service Branches: NEW YORK•CHICAGO•LOS ANGELES *As in all Beckman in struments, your money buys more value than^ in any similar product.
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GREATER CONVENIENCE: The single-beam principle eliminates troublesome, time-wast ing cell- and beam-matching problems. * GREATER VERSATILITY: Greater versatility and simplicity and lower costs are assured, since special cells and attachments need not be duplicated for use in a reference beam. • GREATER ACCURACY: The single-beam principle eliminates problems of making a beam attenuator achromatic, linear and free of vignetting effects. Ρ MINIMUM STRAY LIGHT: Only these single beam instruments use a filter-type beam chopper, reducing stray light effects to a minimum (less than 2 % at 15 microns with the IR-2). ψ MINIMUM SCANNING TIME: Optimum re cording efficiency is achieved because each spectral slit width is traversed in a time proportional to the response period of the recording system. Any other scanning rate loses either resolution, time or accuracy. fc MAXIMUM RESOLUTION: Slit width control has the advantage that the instrument is always working at maximum resolution for the chosen amplification and scanning speed. • FLEXIBILITY OF CONTROL: Operating speed, resolution and chart scales can be easily varied over wide ranges. A single con trol adjusts scanning time per spectral slit width from 1 second to 128 seconds by fac tors of 2. The wavelength motor speed is electronically controlled with no gear shift ing needed to change scanning speed. In addition to recording linearly in wave length, a unique electronic system enables recordings to be made linearly in other func tions such as frequency or log wavelength.
Recorder
Control Unit
1R-2 Spectrophotometer
AmplifierPower Supply
Beckman Instruments include : pH Meters and Electrodes — Spectrophotometers — Radioactivity Meters — Special Instruments
